[Infastructure] Update build to use a local npm package cache from a submodule and build offline (#53975)

* Update build to use a local package cache from a submodule and build 'offline'

Author: wtgodbe

.azure/pipelines/components-e2e-tests.yml

@@ -41,7 +41,7 @@ jobs:
       displayName: Update submodules
     - script: ./restore.sh
       displayName: Run restore.sh
-    - script: npm ci
+    - script: npm ci  --offline
       displayName: NPM install
     - script: npm run build
       displayName: Build JS

.github/dependabot.yml

@@ -45,6 +45,9 @@ updates:
     commit-message:
       prefix: "[main] "
       include: scope
+    ignore:
+      # Don't auto-update the Node-Externals submodule
+      - dependency-name: "Node-Externals*"
     labels:
       - area-infrastructure
 

.gitmodules

@@ -6,3 +6,6 @@
 	path = src/submodules/MessagePack-CSharp
 	url = https://github.com/aspnet/MessagePack-CSharp.git
 	branch = master
+[submodule "Node-Externals"]
+	path = src/submodules/Node-Externals
+	url = https://github.com/dotnet/Node-Externals

.npmrc

@@ -1,2 +1,3 @@
 registry=https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-public-npm/npm/registry/
+cache=./src/submodules/Node-Externals/cache
 always-auth=true

eng/Npm.Workspace.nodeproj

@@ -15,9 +15,14 @@
     <PackageVersion>$(VersionPrefix)$(VersionSuffix)</PackageVersion>
   </PropertyGroup>
 
-  <Target Name="Restore">
+  <Target Name="_VerifyNPMCache">
+    <Message Text="Verifying NPM cache..." Importance="high" />
+    <Exec Command="npm cache verify" WorkingDirectory="$(MSBuildThisFileDirectory).." />
+  </Target>
+
+  <Target Name="Restore" DependsOnTargets="_VerifyNPMCache">
     <Message Text="Restoring NPM packages..." Importance="high" />
-    <Exec Command="npm ci" WorkingDirectory="$(MSBuildThisFileDirectory).." />
+    <Exec Command="npm ci --offline" WorkingDirectory="$(MSBuildThisFileDirectory).." />
   </Target>
 
   <Target Name="Build">

eng/SourceBuild.props

@@ -108,7 +108,7 @@
       WorkingDirectory="$(InnerSourceBuildRepoRoot)" />
 
     <Exec
-      Command="npm ci"
+      Command="npm ci --offline"
       WorkingDirectory="$(InnerSourceBuildRepoRoot)" />
 
   </Target>